these have been out and tested for a few years.
there are about 6 or 7 sizes.
the heaviest weigh in about 6oz.
nice for the price.
good for inshore to tuna.
here a writeup

The most exciting new way to catch fish virtually anywhere in the world. These Mud Hole Exclusive Custom Builder Vertical Jigging rod blanks have been developed to withstand the stresses put on this new fishing application and handle anything you put on the end of it. Experience this amazing new Jigging system with extremely light weight and powerful Custom Builder Vertical Jigging Blanks.

Prototyped and developed in the United States, these rod blanks are constructed from a carbon tape and multi modulus weave mixture along with a single ply of glass fabric